CROSS REFERENCE TO RELATED APPLICATION
TECHNICAL FIELD
[0002] The present disclosure generally relates to mounting systems for gearboxes, such
as gearboxes associated with engines, and more particularly relates to a mounting
system for a gearbox associated with an engine of a vehicle that includes a corrugated
bushing.
BACKGROUND
[0003] Gas turbine engines may be employed to power various devices. For example, a gas
turbine engine may be employed to power a vehicle, such as an aircraft. Typically,
gas turbine engines include accessories that assist in engine operation and in the
operation of the vehicle. These accessories are driven by a gearbox, which is driven
by the gas turbine engine. Generally, the gearbox is mounted to the gas turbine engine.
In certain instances, the gas turbine engine may experience vibrations during operation.
As the gearbox is coupled to the gas turbine engine, the vibration of the gas turbine
engine may impart loads to the gearbox, which is undesirable.
[0004] Accordingly, it is desirable to provide a mounting system for a gearbox, which includes
a corrugated bushing to assist in reducing loads transferred to the gearbox from the
engine. Furthermore, other desirable features and characteristics of the present invention
will become apparent from the subsequent detailed description and the appended claims,
taken in conjunction with the accompanying drawings and the foregoing technical field
and background.
SUMMARY
[0005] According to various embodiments, provided is a mounting system for coupling a gearbox
to an engine. The mounting system includes a sleeve having a first sleeve end opposite
a second sleeve end, an outer perimeter and a sleeve bore defined through the sleeve
from the first sleeve end to the second sleeve end. The mounting system includes a
damping member coupled about the outer perimeter of the sleeve at the first sleeve
end. The mounting system includes a corrugated bushing coupled about the outer perimeter
of the sleeve between the damping member and the second sleeve end.
[0006] The corrugated bushing has a bushing outer perimeter and a bushing inner perimeter,
and at least one chamber is defined between the bushing outer perimeter and the bushing
inner perimeter. The at least one chamber comprises a plurality of hollow chambers
that are spaced apart about the bushing outer perimeter. The at least one chamber
comprises a plurality of hollow chambers that are spaced apart axially from a first
bushing end to a second bushing end of the corrugated bushing. The corrugated bushing
defines a plurality of undulations that extend tangentially about a bushing outer
perimeter of the corrugated bushing. The corrugated bushing defines a plurality of
undulations that extend axially along a bushing outer perimeter of the corrugated
bushing from a first bushing end to a second bushing end. The corrugated bushing includes
a plurality of corrugations, each of the plurality of corrugations includes a sidewall,
a first ramp surface coupled to the sidewall and a second ramp surface coupled to
the first ramp surface, and the second ramp surface is coupled to the sidewall of
an adjacent one of the plurality of corrugations. The sidewall includes a plurality
of undulations. The corrugated bushing includes a plurality of corrugations defined
on a sheet that defines a bushing outer perimeter of the corrugated bushing, each
of the plurality of corrugations includes a first ramp surface and a second ramp surface
coupled to the first ramp surface, and the sheet is coupled to a bushing sleeve that
defines a bushing inner perimeter of the corrugated bushing by a plurality of sidewalls.
Each of the plurality of sidewalls includes a plurality of undulations. The mounting
system includes a mounting housing that defines a coupling bore and a second coupling
bore. The sleeve, the damping member and the corrugated bushing are each configured
to be received within the coupling bore such that the outer perimeter of the sleeve
faces an inner diameter of the coupling bore and a bushing outer perimeter of the
corrugated bushing is spaced apart from the inner diameter of the coupling bore. The
coupling bore is configured to couple the mounting system to the engine and the second
coupling bore is configured to couple the mounting system to the gearbox.
[0007] Also provided is a mounting system for coupling a gearbox to an engine. The mounting
system includes a sleeve having a first sleeve end opposite a second sleeve end, and
a sleeve bore defined through the sleeve from the first sleeve end to the second sleeve
end. The mounting system includes a damping member coupled about the sleeve at the
first sleeve end, and a corrugated bushing coupled about the sleeve between the damping
member and the second sleeve end. The corrugated bushing includes a bushing sleeve
that defines a bushing inner perimeter of the corrugated bushing and a plurality of
corrugations that define a bushing outer perimeter of the corrugated bushing. The
bushing sleeve is coupled about the sleeve and the bushing sleeve is coupled to the
plurality of corrugations by a plurality of sidewalls.
[0008] The plurality of corrugations are defined tangentially about the bushing outer perimeter
of the corrugated bushing. The plurality of corrugations are defined axially from
a first bushing end to a second bushing end. Each of the plurality of sidewalls is
planar. Each of the plurality of sidewalls includes a plurality of undulations. Each
of the plurality of undulations includes at least a first sidewall peak, a second
sidewall peak and a trough defined between the first sidewall peak and the second
sidewall peak in a clockwise direction. The plurality of corrugations, the plurality
of sidewalls and the bushing sleeve cooperate to define a plurality of chambers. The
mounting system includes the gearbox and the gearbox defines a gearbox coupling bore
configured to receive the mounting system such that a bushing outer perimeter of the
corrugated bushing is spaced apart from an inner diameter of the gearbox coupling
bore. The mounting system includes a mounting housing that defines a coupling bore
and a second coupling bore offset from the coupling bore. The sleeve, the damping
member and the corrugated bushing are each configured to be received within the coupling
bore such that an outer perimeter of the sleeve faces an inner diameter of the coupling
bore and the bushing outer perimeter of the corrugated bushing is spaced apart from
the inner diameter of the coupling bore. The coupling bore is configured to couple
the mounting system to the engine and the second coupling bore is configured to couple
the mounting system to the gearbox.
DESCRIPTION OF THE DRAWINGS
[0009] The exemplary embodiments will hereinafter be described in conjunction with the following
drawing figures, wherein like numerals denote like elements, and wherein:
FIG. 1 is a schematic illustration of an engine, such as a gas turbine engine, that
includes a gearbox coupled to the gas turbine engine with a mounting system including
at least one corrugated bushing in accordance with the various teachings of the present
disclosure;
FIG. 1A is an aft end view of the gearbox of FIG. 1 coupled to the gas turbine engine
in accordance with the various teachings of the present disclosure;
FIG. 1B is a cross-sectional view of a first, left mount for coupling the gearbox
to the gas turbine engine, taken along line 1B-1B of FIG. 1A;
FIG. 1C is a cross-sectional view of a second, right mount for coupling the gearbox
to the gas turbine engine, taken along line 1C-1C of FIG. 1A;
FIG. 2 is a perspective view of a mounting housing including the mounting system of
FIG. 1;
FIG. 3 is an exploded view of the mounting system from the mounting housing of FIG.
2;
FIG. 4 is a cross-sectional view of the mounting housing and the mounting system,
taken along line 4-4 of FIG. 2;
FIG. 5 is a perspective view of an exemplary corrugated bushing for use with the mounting
system of FIG. 1;
FIG. 5A is a cross-section of the corrugated bushing of FIG. 5, taken along line 5A-5A
of FIG. 6;
FIG. 6 is an end view of the corrugated bushing of FIG. 5;
FIG. 7 is a perspective view of another exemplary corrugated bushing for use with
the mounting system of FIG. 1;
FIG. 7A is a cross-section of the corrugated bushing of FIG. 7, taken along line 7A-7A
of FIG. 8;
FIG. 8 is an end view of the corrugated bushing of FIG. 7;
FIG. 9 is a perspective view of another exemplary corrugated bushing for use with
the mounting system of FIG. 1;
FIG. 10 is a cross-section of the corrugated bushing of FIG. 9, taken along line 10-10
of FIG. 9; and
FIG. 11 is an end view of the corrugated bushing of FIG. 9.
DETAILED DESCRIPTION
[0010] The following detailed description is merely exemplary in nature and is not intended
to limit the application and uses. Furthermore, there is no intention to be bound
by any expressed or implied theory presented in the preceding technical field, background,
brief summary or the following detailed description. In addition, those skilled in
the art will appreciate that embodiments of the present disclosure may be practiced
in conjunction with any type of system that would benefit from reduced load transfer
through a mounting system, and the use of the mounting system for a gearbox of a gas
turbine engine associated with a vehicle described herein is merely one exemplary
embodiment according to the present disclosure. In addition, while the mounting system
is described herein as being used with a gas turbine engine onboard a vehicle, such
as a bus, motorcycle, train, automobile, marine vessel, aircraft, rotorcraft and the
like, the various teachings of the present disclosure can be used with a gas turbine
engine in other applications. Further, it should be noted that many alternative or
additional functional relationships or physical connections may be present in an embodiment
of the present disclosure. In addition, while the figures shown herein depict an example
with certain arrangements of elements, additional intervening elements, devices, features,
or components may be present in an actual embodiment. It should also be understood
that the drawings are merely illustrative and may not be drawn to scale.
[0011] As used herein, the term "axial" refers to a direction that is generally parallel
to or coincident with an axis of rotation, axis of symmetry, or centerline of a component
or components. For example, in a cylinder or disc with a centerline and generally
circular ends or opposing faces, the "axial" direction may refer to the direction
that generally extends in parallel to the centerline between the opposite ends or
faces. In certain instances, the term "axial" may be utilized with respect to components
that are not cylindrical (or otherwise radially symmetric). For example, the "axial"
direction for a rectangular housing containing a rotating shaft may be viewed as a
direction that is generally parallel to or coincident with the rotational axis of
the shaft. Furthermore, the term "radially" as used herein may refer to a direction
or a relationship of components with respect to a line extending outward from a shared
centerline, axis, or similar reference, for example in a plane of a cylinder or disc
that is perpendicular to the centerline or axis. In certain instances, components
may be viewed as "radially" aligned even though one or both of the components may
not be cylindrical (or otherwise radially symmetric). Furthermore, the terms "axial"
and "radial" (and any derivatives) may encompass directional relationships that are
other than precisely aligned with (e.g., oblique to) the true axial and radial dimensions,
provided the relationship is predominantly in the respective nominal axial or radial
direction. Furthermore, the term "tangential" as used herein may refer to a direction
or a relationship of a component that is perpendicular or normal to the axial and
radial directions in a gas turbine engine in a cylindrical coordinate system. As used
herein, the term "about" denotes within 5% to account for manufacturing tolerances.
[0012] With reference to FIG. 1, a schematic illustration of an exemplary engine, such as
a gas turbine engine 10 is shown, which includes a gearbox 12. The gearbox 12 is coupled
to the gas turbine engine 10 with a mounting system 100 according to various embodiments.
As will be discussed, the mounting system 100 reduces the transfer of loads to the
gearbox 12 experienced during a vibration of the gas turbine engine 10. It should
be noted that while the mounting system 100 is discussed herein as being used to couple
the gearbox 12 to the gas turbine engine 10, the mounting system 100 can be employed
to couple together various components. Moreover, the mounting system 100 may be employed
to couple the gearbox 12 to any suitable engine, such as a turbojet engine, an auxiliary
power unit (APU), etc. Thus, the following description is merely one exemplary use
of the mounting system 100. Moreover, while the gas turbine engine 10 is described
herein as being used with a vehicle, such as an aircraft 8, it will be understood
that the gas turbine engine 10 may be used with any suitable platform, whether mobile
or stationary.
[0013] In this example, the gas turbine engine 10 includes a fan section 14, a compressor
section 16, a combustion section 18, a turbine section 20, and an exhaust section
22. The fan section 14 includes a fan 24 mounted on a rotor 26 that draws air into
the gas turbine engine 10 and accelerates it. A fraction of the accelerated air exhausted
from the fan 24 is directed through an outer (or first) bypass duct 28 and the remaining
fraction of air exhausted from the fan 24 is directed into the compressor section
16.
[0014] In the embodiment of FIG. 1, the compressor section 16 includes a compressor 32 that
raises the pressure of the air directed into it from the fan section 14. However,
in other embodiments, the number of compressors in the compressor section 16 may vary.
In the depicted embodiment, the compressor 32 raises the pressure of the air and directs
the high pressure air into a combustor 36. The fraction of air that entered the first
bypass duct 28 enters a second bypass duct 34.
[0015] In the combustion section 18, which includes the combustor 36, the high pressure
air is mixed with fuel and combusted. The high-temperature combusted air is then directed
into the turbine section 20. The turbine section 20 includes one or more turbines
disposed in axial flow series, for example, a high pressure turbine 38 and a low pressure
turbine 42. However, it will be appreciated that the number of turbines, and/or the
configurations thereof, may vary. In this embodiment, the high-temperature combusted
air from the combustion section 18 expands through and rotates each turbine 38 and
42. The air is then exhausted through a mixing nozzle 44 where it is recombined with
the bypass flow air in the exhaust section 22. As the turbines 38 and 42 rotate, each
drives equipment in the gas turbine engine 10 via concentrically disposed shafts or
spools. In one example, the high pressure turbine 38 drives the compressor 32 via
a high pressure driveshaft 46 and the low pressure turbine 42 drives the fan 24 via
a low pressure driveshaft 50. Generally, the high pressure driveshaft 46 and the low
pressure driveshaft 50 are coaxially arranged along a longitudinal axis L of the gas
turbine engine 10, and each of the high pressure driveshaft 46 and the low pressure
driveshaft 50 have an axis of rotation R, which extends substantially parallel to
and along the longitudinal axis L.
[0016] In the example of FIG. 1, the high pressure driveshaft 46 includes a gear 52. In
this example, the gear 52 is a bevel gear, having a plurality of bevel gear teeth.
The gear 52 is coupled to a towershaft 54 and drives the towershaft 54. In one example,
the towershaft 54 includes a first end 54a and a second end 54b. The first end 54a
includes a gear 56, which in this example, comprises a bevel gear. The gear 56 includes
a plurality of bevel gear teeth, which are meshingly coupled to or engaged with the
plurality of bevel gear teeth of the gear 52. The engagement of gear 56 with gear
52 transfers torque from the high pressure driveshaft 46 to the towershaft 54, and
thus, drives or rotates the towershaft 54. The towershaft 54 is generally coupled
to the gear 52 such that the towershaft 54 extends along an axis of rotation TR, which
is substantially transverse to the axis of rotation R of the high pressure driveshaft
46. One or more bearings or supports may be coupled to the towershaft 54 at or near
the first end 54a to support the towershaft 54 for rotation with the gear 56.
[0017] The second end 54b of the towershaft 54 is coupled to the gearbox 12. In one example,
the second end 54b of the towershaft 54 includes a sleeve 55. The sleeve 55 is coupled
about the second end 54b via splined coupling, for example, although any suitable
joining technique may be employed such that the sleeve 55 rotates in unison with the
towershaft 54. The sleeve 55 may be supported for rotation by a bearing 57, which
is disposed in a housing 59. The housing 59 couples the second end 55b of the sleeve
55 to the gearbox 12 and the bearing 57 supports the sleeve 55 for rotation. The sleeve
55 further includes a gear 58, such as a bevel gear. The gear 58 is disposed at a
second end 55b of the sleeve 55, and includes a plurality of bevel gear teeth. The
plurality of bevel gear teeth are coupled about a perimeter or circumference of the
gear 58. The gear 58 is coupled to a bevel gear contained within the gearbox 12. Generally,
the gear 58 transfers torque from the sleeve 55 and the towershaft 54 to the gearbox
12 to drive various components coupled to the gearbox 12. In one example, the gearbox
12 is mounted within a nacelle N of the gas turbine engine 10.
[0018] As shown in FIG. 1A, a first or left mount 72 and a second or right mount 74 each
cooperate with the front frame 70 of the gas turbine engine 10 to couple the gearbox
12 to the gas turbine engine 10. As will be discussed, the left mount 72 and the right
mount 74 each includes a mounting system 100, which couples the gearbox 12 to the
gas turbine engine 10. In one example, with reference to FIG. 1B, the front frame
70 includes a first left flange or lug 76 spaced apart from a second left flange or
lug 78. Each of the first left lug 76 and the second left lug 78 define a respective
left coupling bore 80a, 80b, which are coaxially aligned. The left mount 72 is coupled
to the first left lug 76 and the second left lug 78 via a mechanical fastener, such
as a bolt 82, that is received through the left coupling bores 80a, 80b and the left
mount 72. With reference to FIG. 1C, the front frame 70 also includes a first right
flange or lug 84 and a second right flange or lug 86. Each of the first right lug
84 and the second right lug 86 extend radially outward from the front frame 70. Each
of the first right lug 84 and the second right lug 86 define a respective right coupling
bore 88a, 88b. The right coupling bores 88a, 88b are coaxially aligned for coupling
to the right mount 74. The first right lug 84 and the second right lug 86 are spaced
apart axially to enable a portion of the right mount 74 to be received between the
first right lug 84 and the second right lug 86. A mechanical fastener, including but
not limited to a bolt 90 may be used to couple the right mount 74 to the front frame
70.
[0019] With reference to FIG. 1A, the gearbox 12 includes a gearbox housing 92 that substantially
surrounds the gears associated with the gearbox 12. The gearbox housing 92 also includes
the left mount 72 and the right mount 74. With reference to FIG. 1B, the left mount
72 defines a left gearbox coupling bore 72a that is coaxially aligned with the left
coupling bores 80a, 80b to receive the bolt 82. With reference to FIG. 1C, the right
mount 74 defines a first right gearbox flange or lug 94, a second right gearbox flange
or lug 96 and a mounting housing 98. The first right gearbox lug 94 and the second
right gearbox lug 96 each extend radially outward from the gearbox housing 92 and
define a respective right gearbox bore 94a, 96a. The right gearbox bores 94a, 96a
are coaxially aligned for receiving a mechanical fastener, such as a bolt 97, to couple
the mounting housing 98 to the first right gearbox lug 94 and the second right gearbox
lug 96. The first right gearbox lug 94 and the second right gearbox lug 96 are spaced
apart axially to enable a portion of the mounting housing 98 to be received between
the first right gearbox lug 94 and the second right gearbox lug 96. Each of the left
mount 72 and the right mount 74 includes the mounting system 100 that is coupled or
positioned about the bolt 82, 90 to reduce the transfer of loads to the gearbox 12
experienced during a vibration of the gas turbine engine 10. In this example, the
left mount 72 includes the mounting system 100 coupled to the left gearbox coupling
bore 72a, and the right mount 74 includes the mounting system 100 coupled to the mounting
housing 98 for coupling the gearbox 12 to the gas turbine engine 10.
[0020] With reference to FIGS. 2 and 3, the mounting housing 98 and the mounting system
100 associated with the right mount 74 is shown in greater detail. It should be noted
that the mounting system 100 associated with the left mount 72 is the same as the
mounting system 100 associated with the right mount 74 and for ease of description
the mounting system 100 associated with the right mount 74 will be discussed in detail
herein with the understanding that the mounting system 100 associated with the left
mount 72 is the same. In one example, the mounting system 100 includes at least one
or a pair of first bushings 104 (FIG. 3) and at least one or a pair of second, corrugated
bushings 106 (FIG. 3).
[0021] The mounting housing 98 is monolithic, one-piece, or unitary and is composed of a
metal or metal alloy. The mounting housing 98 may be cast, forged, machined, additively
manufactured, etc. The mounting housing 98 includes a gearbox coupling portion 110
and an engine coupling portion 112. With reference to FIG. 2, the gearbox coupling
portion 110 includes a first gearbox coupling flange 114 and a second gearbox coupling
flange 116. The gearbox coupling flanges 114, 116 extend from the engine coupling
portion 112. The gearbox coupling flanges 114, 116 are substantially cylindrical,
but the gearbox coupling flanges 114, 116 may have any desired shape. The first gearbox
coupling flange 114 is spaced a distance apart from the second gearbox coupling flange
116 along a mounting longitudinal axis ML of the mounting system 100. The mounting
longitudinal axis ML is parallel to the longitudinal axis L (FIG. 1) of the gas turbine
engine 10. Generally, each of the gearbox coupling flanges 114, 116 are spaced apart
to enable the first right gearbox lug 94 and the second right gearbox lug 96 to be
received between the gearbox coupling flanges 114, 116. Each of the gearbox coupling
flanges 114, 116 includes a respective first coupling flange end 120, 122 opposite
a respective second coupling flange end 124, 126 and a respective coupling bore 128,
130. The first coupling flange end 120 of the first gearbox coupling flange 114 is
coupled proximate the first right gearbox lug 94 and the second right gearbox lug
96 is coupled between the second coupling flange end 124 of the first gearbox coupling
flange 114 and the first coupling flange end 122 of the second gearbox coupling flange
116 when the mounting housing 98 is coupled to the gearbox 12 (FIG. 1). The coupling
bores 128, 130 each extends through the respective gearbox coupling flange 114, 116
from the first coupling flange end 120, 122 to the second coupling flange end 124,
126. The coupling bores 128, 130 of the respective gearbox coupling flange 114, 116
are coaxially aligned with each of the right gearbox bores 94a, 96a of the first right
gearbox lug 94 and the second right gearbox lug 96 to enable the bolt 97 to be inserted
through the coupling bores 128, 130 and the right gearbox bores 94a, 96a to couple
the gearbox 12 to the right mount 74 (FIG. 1). In this example, the first gearbox
coupling flange 114 extends for a distance along the mounting longitudinal axis ML
that is different and greater than a distance the second gearbox coupling flange 116
extends along the mounting longitudinal axis ML.
[0022] In one example, the gearbox coupling portion 110 extends forward of or axially in
front of the engine coupling portion 112. The first gearbox coupling flange 114 may
include a shelf or flat surface 114a, which enables the bolt 97 to be inserted through
the engine coupling portion 112. Thus, generally, the engine coupling portion 112
may be recessed relative to the gearbox coupling portion 110. The engine coupling
portion 112 is substantially cylindrical. The engine coupling portion 112 includes
a first engine coupling end 132 opposite a second engine coupling end 134, and a coupling
bore or engine coupling bore 136. In one example, the first engine coupling end 132
includes a notched surface 132a to assist in coupling the bolt 90 to the engine coupling
portion 112. The engine coupling bore 136 is defined to extend through the engine
coupling portion 112 from the first engine coupling end 132 to the second engine coupling
end 134. The engine coupling bore 136 is spaced apart from and offset from the right
gearbox bores 94a, 96a. With reference to FIG. 4, the engine coupling bore 136 is
sized to receive the pair of first bushings 104 and the pair of corrugated bushings
106. In the example of the left mount 72, the pair of first bushings 104 are each
received within the left gearbox coupling bore 72a (FIG. 1B).
[0023] The pair of first bushings 104 each include a sleeve 140 and a damping member 142.
The sleeve 140 is composed of a metal or metal alloy, and is cast, forged, machined,
additively manufactured, etc. The sleeve 140 extends from a first sleeve end 144 to
an opposite second sleeve end 146. The sleeve 140 defines a sleeve bore 148, which
is defined through the sleeve 140 from the first sleeve end 144 to the second sleeve
end 146. In this example, the pair of first bushings 104 are arranged within the engine
coupling bore 136 so as to be symmetric about an axis that is perpendicular to the
mounting longitudinal axis ML. Stated another way, the second sleeve ends 146 of the
first bushings 104 are adjacent to or in contact with each other. The first sleeve
end 144 includes a sleeve flange 150, which extends about a perimeter or circumference
of the sleeve 140. The sleeve flange 150 is proximate or adjacent to the respective
one of the engine coupling ends 132, 134 when the first bushings 104 are coupled to
the engine coupling bore 136. Generally, a majority of an outer perimeter of the sleeve
140 (from the sleeve flange 150 to the second sleeve end 146) faces the engine coupling
bore 136 when the first bushings 104 are coupled to the engine coupling bore 136.
The sleeve flange 150 has a diameter, which is different and greater than a diameter
of the second sleeve end 146. The diameter of the sleeve flange 150 is also different
and greater than a diameter of a majority of the damping member 142. The sleeve flange
150 assists in coupling the damping member 142 to the sleeve 140. The second sleeve
end 146 includes a collar 152. The collar 152 extends radially outward at the second
sleeve end 146 to provide a contact surface for the respective corrugated bushing
106. Between the first sleeve end 144 and the second sleeve end 146, the sleeve 140
includes a second collar 154. The second collar 154 extends radially outward from
the sleeve 140 proximate the damping member 142. The second collar 154 provides a
contact surface for the respective corrugated bushing 106, and also assists in the
formation of the damping member 142 onto the sleeve 140 by providing a locating feature.
The sleeve bore 148 is sized to retain the bolt 90, and each of the sleeve bores 148
are coaxially aligned when the first bushings 104 are coupled to the engine coupling
portion 112.
[0024] The damping member 142 is formed onto the sleeve 140. The damping member 142 is composed
of a polymer based material, including, but not limited to an elastomer, such as acrylonitrile
butadiene (Nbr) Rubber. In one example, the damping member 142 is overmolded onto
an outer perimeter of the sleeve 140 at the first sleeve end 144 between the sleeve
flange 150 and the second collar 154. In this example, the damping member 142 is substantially
cylindrical and forms an elastomeric bushing. The damping member 142 has a first damping
end 156 opposite a second damping end 158, and defines a damping bore 160 that extends
from the first damping end 156 to the second damping end 158. The first damping end
156 includes a damping flange 162, which extends radially outward at the first damping
end 156. Generally, the damping flange 162 has a diameter that is about equal to the
diameter of the sleeve flange 150. The damping flange 162 contacts the respective
one of the first engine coupling end 132 and the second engine coupling end 134 of
the engine coupling portion 112 when the first bushings 104 are coupled to the engine
coupling portion 112. The second damping end 158 includes a taper 164. The taper 164
transitions a diameter of the damping member 142 toward the diameter of the sleeve
140 proximate the second sleeve end 146. By providing the damping member 142 with
the taper 164, a volume 166 is defined between the damping member 142 and the engine
coupling bore 136 when the first bushings 104 are coupled to the engine coupling portion
112. The damping bore 160 surrounds the sleeve 140 and is defined by the formation
of the damping member 142 about the sleeve 140.
[0025] With reference to FIG. 3, the corrugated bushings 106 are each received within the
engine coupling bore 136 of the mounting housing 98 or the left gearbox coupling bore
72a of the left mount 72 (FIG. 1B). Each of the corrugated bushings 106 include a
first bushing end 170 opposite a second bushing end 172, a plurality of corrugations
174 and define a bushing bore 176 that extends from the first bushing end 170 to the
second bushing end 172. Each of the corrugated bushings 106 are composed of a metal
or metal alloy, and may be cast, forged, stamped, additively manufactured, etc. The
corrugated bushings 106 may also be composed of a polymer based material, if desired,
and may be molded, additively manufactured, etc. Each of the corrugated bushings 106
may be formed so as to be monolithic, one-piece, or unitary, but the corrugations
174 may be formed separately and coupled about a bushing sleeve 178 that defines the
bushing bore 176 to form the corrugated bushings 106, if desired. The corrugated bushing
106 is substantially cylindrical. With reference to FIG. 4, the first bushing end
170 is coupled adjacent to the damping member 142 and is coupled to the second collar
154 when the mounting system 100 is assembled. The second bushing end 172 is coupled
to the collar 152 when the mounting system 100 is assembled.
[0026] With reference to FIGS. 5 and 5A, one of the corrugated bushings 106 is shown in
greater detail. It should be noted that while one of the corrugated bushings 106 is
shown in detail herein, both of the corrugated bushings 106 are the same. The corrugations
174 define an exterior surface of each of the corrugated bushings 106, and extend
from the first bushing end 170 to the second bushing end 172. With reference to FIG.
5, the corrugations 174 extend about a perimeter or circumference of the corrugated
bushing 106 such that the corrugations 174 are defined in a tangential direction.
The corrugations 174 enable the corrugated bushing 106 to flex upon an application
of a load above a predetermined threshold. In this example, with reference to FIG.
6, the corrugations 174 are composed of a plurality of sidewalls 180, a plurality
of first ramp surfaces 182 and a plurality of second ramp surfaces 184. In this example,
the sidewalls 180 extend radially and axially from the bushing sleeve 178 that surrounds
and defines the bushing bore 176. The sidewalls 180 are spaced apart about the perimeter
or circumference of the bushing bore 176. In one example, the sidewalls 180 are planar,
straight, or flat, and have a first end coupled to or integrally formed with the bushing
sleeve 178 and an opposite end coupled to or integrally formed with a respective one
of the ramp surfaces 182, 184.
[0027] Each of the first ramp surfaces 182 extends at an angle relative to the respective
sidewall 180. An angle α is defined between the respective first ramp surface 182
and a reference line RL that is perpendicular to the respective sidewall 180. In one
example, the angle α is an acute angle, and is about 45 degrees. Each of the first
ramp surfaces 182 extends straight from the respective sidewall 180 at the angle α,
and is coupled to or integrally formed with a respective one of the second ramp surfaces
184. Each of the second ramp surfaces 184 extends at an angle relative to the respective
sidewall 180. An angle β is defined between the respective second ramp surface 184
and a second reference line RL2 that is perpendicular to the respective sidewall 180.
In one example, the angle β is an acute angle, and is about negative 45 degrees. Generally,
the angle α and the angle β are equal and opposite angles.
[0028] Each of the second ramp surfaces 184 extends straight from the respective sidewall
180 at the angle β, and is coupled to or integrally formed with a respective one of
the first ramp surfaces 182. Each of the respective first ramp surfaces 182 and the
second ramp surfaces 184 are coupled together at a peak 186. The peaks 186 are spaced
apart by a pitch or width W, which is the pitch or the width W of the corrugations
174. The line at which the respective sidewall 180 is coupled to or integrally formed
with the respective first ramp surface 182 and the second ramp surface 184 defines
a trough 188 of the corrugations 174. A depth DC of the corrugations 174 is defined
as a distance between the peak 186 and the trough 188. In this example, the depth
DC and the width W of the corrugations 174 is the same about the perimeter or circumference
of the corrugated bushing 106, but in other examples, the width W and/or the depth
DC may vary about the circumference. The alternating of the peaks 186 and the troughs
188 about the perimeter of the corrugated bushing 106 defines a plurality of undulations
spaced apart about a bushing outer perimeter 190 in the tangential direction.
[0029] In this example, each of the corrugated bushings 106 has the bushing outer perimeter
190 defined by the corrugations 174, and a bushing inner perimeter 192 defined by
the bushing bore 176. The spaced apart sidewalls 180 and the ramp surfaces 182, 184
of the corrugations 174 cooperate with the bushing sleeve 178 to define at least one
or a plurality of chambers 194 that are spaced apart about the perimeter or circumference
of the corrugated bushing 106. In this example, each of the chambers 194 are hollow,
however, in other examples, the chambers 194 may be solid or porous. Each chamber
194 is defined between the bushing outer perimeter 190 and the bushing inner perimeter
192. Each chamber 194 is also discrete or not in communication with an adjacent chamber
194. The chambers 194 assist in reducing a stiffness associated with the corrugated
bushing 106.
[0030] Generally, the corrugated bushings 106 have a stiffness that is about equal to a
stiffness of the damping member 142. The stiffness of the corrugated bushings 106
is predetermined such that the corrugated bushings 106 are inhibited from becoming
a primary load path for load transfer between the gearbox 12 and the gas turbine engine
10. In one example, each of the corrugated bushings 106 has a stiffness of about 100
pound force per inch to about 60000 pound force per inch, while the damping member
142 has a stiffness of about 100 pound force per inch to about 60000 pound force per
inch based on the operating conditions associated with the gas turbine engine 10.
By providing the corrugated bushing 106 with the stiffness about equal to than the
stiffness of the damping member 142, the corrugated bushing 106 may deflect to assist
in sharing a load introduced to the mounting system 100 by a vibration of the gas
turbine engine 10. This reduces an amount of load experienced by the damping member
142, which in turn, reduces an amount of compression of the damping member 142. The
reduction in the amount of compression of the damping member 142 enables the damping
member 142 to provide higher damping, which reduces an amount of load transferred
from the mounting system 100 to the gearbox 12. The reduction in the amount of compression
of the damping member 142 also improves a life expectancy of the damping member 142.
[0031] The bushing sleeve 178 defines the bushing bore 176. The bushing sleeve 178 is cylindrical,
and the corrugations 174 are coupled to the bushing sleeve 178 on a surface opposite
the bushing bore 176. With reference back to FIG. 4, the bushing bore 176 is sized
to receive the sleeve 140 proximate and at the second sleeve end 146 such that the
respective corrugated bushing 106 is coupled about an outer perimeter or circumference
of the sleeve 140 between the damping member 142 and the second sleeve end 146. Generally,
the bushing bore 176 coupled to the sleeve 140 so as to extend from the collar 152
to the second collar 154. The corrugated bushings 106 extend for a distance defined
between the bushing inner perimeter 192 and the bushing outer perimeter 190 that is
sized to enable the corrugated bushings 106 to be positioned between the sleeve 140
and a sidewall of the engine coupling bore 136 or the left gearbox coupling bore 72a
(FIG. 1B). In one example, the distance is equal to or less than about 0.23 inches
(in.). In one example, the distance is sized to define or create a gap 195 between
the bushing outer perimeter 190 and the engine coupling bore 136 or the left gearbox
coupling bore 72a (FIG. 1B). The gap 195 inhibits the corrugated bushings 106 from
becoming a load bearing member during a normal operation of the gas turbine engine
10. When the gas turbine engine 10 experiences vibrations, the gap 195 is closed and
the corrugated bushings 106 become part of the load path. In other embodiments, the
bushing outer perimeter 190 may contact the engine coupling bore 136 or the left gearbox
coupling bore 72a (FIG. 1B).
[0032] It should be noted that in other embodiments, the corrugated bushings 106 may be
configured differently to share the load with the damping members 142 of the first
bushings 104. For example, with reference to FIGS. 7 and 8, a corrugated bushing 306
is shown for use with the mounting system 100. As the corrugated bushing 306 includes
components that are the same or similar to components of the corrugated bushing 106
discussed with regard to FIGS. 1-6, the same reference numerals will be used to denote
the same or similar components. In the example of FIG. 7, the mounting system 100
would include a pair of the corrugated bushings 306, which are arranged and coupled
to the sleeves 140 of the respective first bushings 104 as discussed with regard to
FIGS. 1-6. It should be noted that while one of the corrugated bushings 306 is shown
in detail in FIG. 7, both of the corrugated bushings 306 for use with the mounting
system 100 are the same.
[0033] The corrugated bushings 306 are each received within the engine coupling bore 136
(FIG. 4) of the mounting housing 98 or the left gearbox coupling bore 72a of the left
mount 72 (FIG. 1B). Each of the corrugated bushings 306 include a first bushing end
370 opposite a second bushing end 372, a plurality of corrugations 374 and define
the bushing bore 176 that extends from the first bushing end 370 to the second bushing
end 372. Each of the corrugated bushings 306 are composed of a metal or metal alloy,
and may be cast, forged, stamped, additively manufactured, etc. The corrugated bushings
306 may also be composed of a polymer based material, if desired, and may be molded,
additively manufactured, etc. Each of the corrugated bushings 306 may be formed so
as to be monolithic, one-piece, or unitary, but the corrugations 374 may be formed
separately and coupled about the bushing sleeve 178 that defines the bushing bore
176 to form the corrugated bushings 306, if desired. The corrugated bushing 306 is
substantially cylindrical. The first bushing end 370 is coupled adjacent to the damping
member 142 and is coupled to the second collar 154 when the mounting system 100 is
assembled (FIG. 4). The second bushing end 372 is coupled to the collar 152 when the
mounting system 100 is assembled (FIG. 4).
[0034] With reference to FIGS. 7 and 7A, the corrugations 374 define an exterior surface
of the corrugated bushing 306, and extend from the first bushing end 370 to the second
bushing end 372. The corrugations 374 extend about a perimeter or circumference of
the corrugated bushing 306 and undulate in a tangential direction. The corrugations
374 enable the corrugated bushing 306 to flex upon an application of a load above
a predetermined threshold. In this example, with reference to FIG. 8, the corrugations
374 are composed of a plurality of sidewalls 380, a plurality of first ramp surfaces
382 and a plurality of second ramp surfaces 384. In this example, the sidewalls 380
extend radially and axially from the bushing sleeve 178 that surrounds and defines
the bushing bore 176. The sidewalls 380 are spaced apart about the perimeter or circumference
of the bushing bore 176. In one example, the sidewalls 380 are wavy or define at least
one or a plurality of undulations 385. In this example, the plurality of undulations
385 are defined by a first sidewall peak 387, a second sidewall peak 389 and a sidewall
trough 391 in a clockwise direction. The sidewall trough 391 is defined between the
first sidewall peak 387 and the second sidewall peak 389. It should be noted that
the plurality of undulations 385 may be defined differently, if desired, and for example,
may include two sidewall troughs separated by a sidewall peak. Each of the sidewalls
380 has a first end coupled to or integrally formed with the bushing sleeve 178 and
an opposite end coupled to or integrally formed with a respective one of the ramp
surfaces 382, 384. The plurality of undulations 385 defined on the sidewalls 380 provide
an additional reduction in stiffness of the corrugated bushing 306.
[0035] Each of the first ramp surfaces 382 extends at an angle relative to the respective
sidewall 380. An angle α3 is defined between the respective first ramp surface 382
and a reference line RL3 that is perpendicular to a line that extends along an intersection
of the respective sidewall 380 with the respective first ramp surface 382. In one
example, the angle α3 is an acute angle, and is about 45 degrees. Each of the first
ramp surfaces 382 extends straight from the respective sidewall 380 at the angle α3,
and is coupled to or integrally formed with a respective one of the second ramp surfaces
384. Each of the second ramp surfaces 384 extends at an angle relative to the respective
sidewall 380. An angle β3 is defined between the respective second ramp surface 384
and a second reference line RL6 that is perpendicular a line that extends along an
intersection of the respective sidewall 380 with the respective second ramp surface
384. In one example, the angle β3 is an acute angle, and is about negative 45 degrees.
Generally, the angle α3 and the angle β3 are equal and opposite angles.
[0036] Each of the second ramp surfaces 384 extends straight from the respective sidewall
380 at the angle β3, and is coupled to or integrally formed with a respective one
of the first ramp surfaces 382. Each of the respective first ramp surfaces 382 and
the second ramp surfaces 384 are coupled together at the peak 186. The peaks 186 are
spaced apart by the pitch or width W, which is the pitch or the width W of the corrugations
374. The line at which the respective sidewall 380 is coupled to or integrally formed
with the respective first ramp surface 382 and the second ramp surface 384 defines
a trough 388 of the corrugations 374. A depth DC3 of the corrugations 374 is defined
as a distance between the peak 186 and the trough 388. In this example, the depth
DC3 and the width W of the corrugations 374 is the same about the perimeter or circumference
of the corrugated bushing 306, but in other examples, the width W and/or the depth
DC3 may vary about the circumference. The alternating of the peaks 186 and the troughs
388 about the perimeter of the corrugated bushing 306 defines a plurality of undulations
spaced apart about a bushing outer perimeter 390 in the tangential direction.
[0037] In this example, each of the corrugated bushings 306 has a bushing outer perimeter
390 defined by the corrugations 374, and the bushing inner perimeter 192 defined by
the bushing bore 176. The spaced apart sidewalls 380 and the ramp surfaces 382, 384
of the corrugations 374 cooperate with the bushing sleeve 178 to define at least one
or a plurality of chambers 394 that are spaced apart about the perimeter or circumference
of the corrugated bushing 306. In this example, each of the chambers 394 are hollow,
however, in other examples, the chambers 394 may be solid or porous. Each chamber
394 is defined between the bushing outer perimeter 390 and the bushing inner perimeter
192. Each chamber 394 is also discrete or not in communication with an adjacent chamber
394. The chambers 394 assist in reducing a stiffness associated with the corrugated
bushing 306.
[0038] Generally, the corrugated bushings 306 have a stiffness that is about equal to the
stiffness of the damping member 142. The stiffness of the corrugated bushings 306
is predetermined such that the corrugated bushings 306 are inhibited from becoming
a primary load path for load transfer between the gearbox 12 and the gas turbine engine
10. In one example, each of the corrugated bushings 306 has the stiffness of about
100 pound force per inch to about 60000 pound force per inch, while the damping member
142 has the stiffness of about 100 pound force per inch to about 60000 pound force
per inch based on the operating conditions associated with the gas turbine engine
10. By providing the corrugated bushing 306 with the stiffness about equal to the
stiffness of the damping member 142, the corrugated bushing 306 may deflect to assist
in sharing a load introduced to the mounting system 100 by a vibration of the gas
turbine engine 10. This reduces an amount of load experienced by the damping member
142, which in turn, reduces an amount of compression of the damping member 142. The
reduction in the amount of compression of the damping member 142 enables the damping
member 142 to provide higher damping, which reduces an amount of load transferred
from the mounting system 100 to the gearbox 12. The reduction in the amount of compression
of the damping member 142 also improves a life expectancy of the damping member 142.
[0039] The bushing sleeve 178 is cylindrical, and the corrugations 374 are coupled to the
bushing sleeve 178 on a surface opposite the bushing bore 176. The bushing bore 176
is sized to receive the sleeve 140 proximate and at the second sleeve end 146 such
that the respective corrugated bushing 306 is coupled about an outer perimeter or
circumference of the sleeve 140 between the damping member 142 and the second sleeve
end 146 (FIG. 4). Generally, the bushing bore 176 coupled to the sleeve 140 so as
to extend from the collar 152 to the second collar 154. The corrugated bushings 306
extend for a distance defined between the bushing inner perimeter 192 and the bushing
outer perimeter 390 that is sized to enable the corrugated bushings 306 to be positioned
between the sleeve 140 and a sidewall of the engine coupling bore 136 (FIG. 4) or
the left gearbox coupling bore 72a (FIG. 1B). In one example, the distance is equal
to or less than about 0.23 inches (in.). In one example, the distance may be sized
to define or create the gap 195 (FIG. 4) between the bushing outer perimeter 390 and
the engine coupling bore 136 or the left gearbox coupling bore 72a (FIG. 1B). In other
embodiments, the bushing outer perimeter 390 may contact the engine coupling bore
136 or the left gearbox coupling bore 72a (FIG. 1B).
[0040] It should be noted that in other embodiments, the corrugated bushings 106 may be
configured differently to share the load with the damping members 142 of the first
bushings 104. For example, with reference to FIGS. 9-11, a corrugated bushing 406
is shown for use with the mounting system 100. As the corrugated bushing 406 includes
components that are the same or similar to components of the corrugated bushing 406
discussed with regard to FIGS. 1-6, the same reference numerals will be used to denote
the same or similar components. In the example of FIG. 9, the mounting system 100
would include a pair of the corrugated bushings 406, which are arranged and coupled
to the sleeves 140 of the respective first bushings 104 as discussed with regard to
FIGS. 1-6. It should be noted that while one of the corrugated bushings 406 is shown
in detail in FIG. 9, both of the corrugated bushings 406 for use with the mounting
system 100 are the same.
[0041] The corrugated bushings 406 are each received within the engine coupling bore 136
(FIG. 4) of the mounting housing 98 or the left gearbox coupling bore 72a of the left
mount 72 (FIG. 1B). Each of the corrugated bushings 406 include a first bushing end
470 opposite a second bushing end 472, a plurality of corrugations 474, a plurality
of sidewalls 476 and define the bushing bore 176 that extends from the first bushing
end 470 to the second bushing end 472. Each of the corrugated bushings 406 are composed
of a metal or metal alloy, and may be cast, forged, stamped, additively manufactured,
etc. The corrugated bushings 406 may also be composed of a polymer based material,
if desired, and may be molded, additively manufactured, etc. Each of the corrugated
bushings 406 may be formed so as to be monolithic, one-piece, or unitary, and or may
be formed as multiple pieces and coupled together via welding, adhesives, etc., if
desired. The corrugated bushing 406 is substantially cylindrical. The first bushing
end 470 is coupled adjacent to the damping member 142 and is coupled to the second
collar 154 when the mounting system 100 is assembled (FIG. 4). The second bushing
end 472 is coupled to the collar 152 when the mounting system 100 is assembled (FIG.
4).
[0042] With reference to FIG. 9, the corrugations 474 define an exterior surface of each
of the corrugated bushings 406, and extend from the first bushing end 470 to the second
bushing end 472. The corrugations 474 extend about a perimeter or circumference of
the corrugated bushing 406, and undulate in an axial direction or in a direction parallel
to the mounting longitudinal axis ML. The corrugations 474 enable the corrugated bushing
406 to flex upon an application of a load above a predetermined threshold. In this
example, with reference to FIG. 10, the corrugations 474 are defined along a substantially
cylindrical sheet 481, and are composed of a plurality of first ramp surfaces 482
and a plurality of second ramp surfaces 484. Each of the first ramp surfaces 482 extends
at an angle relative to the mounting longitudinal axis ML. An angle α4 is defined
between the respective first ramp surface 482 and a reference line RL4 that is parallel
to the mounting longitudinal axis ML. In one example, the angle α4 is an acute angle,
and is about 45 degrees. Each of the first ramp surfaces 482 extends straight from
the respective sidewall 480 at the angle α4, and is coupled to or integrally formed
with a respective one of the second ramp surfaces 484. Each of the second ramp surfaces
484 extends at an angle relative to the mounting longitudinal axis ML. An angle β4
is defined between the respective second ramp surface 484 and a second reference line
RL8 that is parallel to the mounting longitudinal axis ML. In one example, the angle
β4 is an acute angle, and is about negative 45 degrees. Generally, the angle α4 and
the angle β4 are equal and opposite angles.
[0043] Each of the second ramp surfaces 484 extends straight from the respective sidewall
480 at the angle β4, and is coupled to or integrally formed with a respective one
of the first ramp surfaces 482. Each of the respective first ramp surfaces 482 and
the second ramp surfaces 484 are coupled together at a peak 486. The peaks 486 are
spaced apart by a pitch or width W4, which is the pitch or the width W4 of the corrugations
474. The line at which the respective sidewall 480 is coupled to or integrally formed
with the respective first ramp surface 482 and the second ramp surface 484 defines
a trough 488 of the corrugations 474. A depth DC4 of the corrugations 474 is defined
as a distance between the peak 486 and the trough 488. In this example, the depth
DC4 and the width W4 of the corrugations 474 is the same about the perimeter or circumference
of the corrugated bushing 406, but in other examples, the width W4 and/or the depth
DC4 may vary about the circumference. The alternating of the peaks 486 and the troughs
488 about the perimeter of the corrugated bushing 406 defines a plurality of undulations
spaced apart about a bushing outer perimeter 490 in the axial direction.
[0044] The sidewalls 476 interconnect the corrugations 474 with the bushing sleeve 178.
In this example, the sidewalls 476 extend radially and axially between the bushing
sleeve 178 and the sheet 481. With reference to FIG. 11, the sidewalls 476 are spaced
apart about the perimeter or circumference of the bushing bore 176 defined by the
bushing sleeve 178. In one example, the sidewalls 476 are wavy or define at least
one or a plurality of undulations 485. In this example, the plurality of undulations
485 are defined by a first sidewall peak 487, a second sidewall peak 489 and a sidewall
trough 491 in a clockwise direction. The sidewall trough 491 is defined between the
first sidewall peak 487 and the second sidewall peak 489. It should be noted that
the plurality of undulations 485 may be defined differently, if desired, and for example,
may include two sidewall troughs separated by a sidewall peak. Each of the sidewalls
476 has a first end coupled to or integrally formed with the bushing sleeve 178 and
an opposite end coupled to or integrally formed with a respective trough 488 of the
sheet 481 (FIG. 10). The plurality of undulations 485 defined on the sidewalls 476
provide an additional reduction in stiffness of the corrugated bushing 406.
[0045] In this example, with reference to FIG. 10, each of the corrugated bushings 406 has
a bushing outer perimeter 490 defined by the corrugations 474, and the bushing inner
perimeter 192 defined by the bushing bore 176. The spaced apart sidewalls 476 and
the troughs 488 of the corrugations 474 cooperate with the bushing sleeve 178 to define
at least one or a plurality of chambers 494 that are spaced apart about the perimeter
or circumference of the corrugated bushing 406. In this example, each of the chambers
494 are hollow, however, in other examples, the chambers 494 may be solid or porous.
Each chamber 494 is defined between the bushing outer perimeter 490 and the bushing
inner perimeter 192. Each chamber 494 is also discrete or not in communication with
an adjacent chamber 494. The chambers 494 assist in reducing a stiffness associated
with the corrugated bushing 406.
[0046] Generally, the corrugated bushings 406 have a stiffness that is about equal to the
stiffness of the damping member 142. The stiffness of the corrugated bushings 406
is predetermined such that the corrugated bushings 406 are inhibited from being a
primary load path for load transfer between the gearbox 12 and the gas turbine engine
10. In one example, each of the corrugated bushings 406 has the stiffness of about
100 pound force per inch to about 60000 pound force per inch, while the damping member
142 has the stiffness of about 100 pound force per inch to about 60000 pound force
per inch based on the operating conditions associated with the gas turbine engine
10. By providing the corrugated bushing 406 with the stiffness about equal to the
stiffness of the damping member 142, the corrugated bushing 406 may deflect to assist
in sharing a load introduced to the mounting system 100 by a vibration of the gas
turbine engine 10. This reduces an amount of load experienced by the damping member
142, which in turn, reduces an amount of compression of the damping member 142. The
reduction in the amount of compression of the damping member 142 enables the damping
member 142 to provide higher damping, which reduces an amount of load transferred
from the mounting system 100 to the gearbox 12. The reduction in the amount of compression
of the damping member 142 also improves a life expectancy of the damping member 142.
[0047] The bushing sleeve 178 is cylindrical, and the corrugations 374 are coupled to the
bushing sleeve 178 on a surface opposite the bushing bore 176. The bushing bore 176
is sized to receive the sleeve 140 proximate and at the second sleeve end 146 such
that the respective corrugated bushing 406 is coupled about an outer perimeter or
circumference of the sleeve 140 between the damping member 142 and the second sleeve
end 146 (FIG. 4). Generally, the bushing bore 176 coupled to the sleeve 140 so as
to extend from the collar 152 to the second collar 154. The corrugated bushings 406
extend for a distance defined between the bushing inner perimeter 192 and the bushing
outer perimeter 490 that is sized to enable the corrugated bushings 406 to be positioned
between the sleeve 140 and a sidewall of the engine coupling bore 136 (FIG. 4) or
the left gearbox coupling bore 72a (FIG. 1B). In one example, the distance is equal
to or less than about 0.23 inches (in.). In one example, the distance may be sized
to define or create the gap 195 (FIG. 4) between the bushing outer perimeter 490 and
the engine coupling bore 136 or the left gearbox coupling bore 72a (FIG. 1B). In other
embodiments, the bushing outer perimeter 490 may contact the engine coupling bore
136 or the left gearbox coupling bore 72a (FIG. 1B).
[0048] With refence back to FIG. 3, in order to assemble the mounting system 100, in one
example, with the first bushings 104 formed with the damping member 142 coupled to
the sleeve 140 and the corrugated bushings 106, 306, 406 formed, the corrugated bushings
106, 306, 406 are coupled to the sleeve 140 so as to be between the second sleeve
end 146 and the damping member 142 of the respective one of the first bushings 104.
In the example of the right mount 74, with reference to FIG. 1C, with the corrugated
bushings 106, 306, 406 coupled to the first bushings 104, one of the first bushings
104, including one of the corrugated bushings 106, 306, 406, is inserted into the
engine coupling bore 136 at the first engine coupling end 132, and the other of the
first bushings 104, including the other one of the corrugated bushings 106, 306, 406,
is inserted into the engine coupling bore 136 at the second engine coupling end 134.
The first bushings 104 are advanced within the engine coupling bore 136 until the
respective damping flange 162 contacts the respective one of the first engine coupling
end 132 and the second engine coupling end 134. In the example of the left mount 72,
with reference to FIG. 1B, with the corrugated bushings 106, 306, 406 coupled to the
first bushings 104, one of the first bushings 104, including one of the corrugated
bushings 106, 306, 406, is inserted into an end of the left gearbox coupling bore
72a, and the other of the first bushings 104, including the other one of the corrugated
bushings 106, 306, 406, is inserted into an opposite end of the left gearbox coupling
bore 72a. The first bushings 104 are advanced within the left gearbox coupling bore
72a until the respective damping flange 162 contacts the respective end of the left
gearbox coupling bore 72a.
[0049] With the mounting system 100 assembled to the mounting housing 98, with reference
to FIG. 1C, in one example, the gearbox coupling portion 110 is coupled to the gearbox
12 with the bolt 97. Generally, the mounting housing 98 is coupled to the gearbox
12 such that the gearbox coupling flanges 114, 116 are adjacent to and interleaved
with the right gearbox lugs 94, 96. With the right gearbox bores 94a, 96a coaxially
aligned with the coupling bores 128, 130, the bolt 97 is inserted through the gearbox
coupling portion 110 to couple the gearbox 12 to the mounting housing 98. With the
gearbox 12 coupled to the mounting housing 98, the engine coupling portion 112 may
be positioned between the right lugs 84, 86. With the right coupling bores 88a, 88b
coaxially aligned with the sleeve bores 148, the bolt 90 is inserted through the engine
coupling portion 112 to couple the gas turbine engine 10 to the mounting housing 98.
With reference to FIG. 1B, in one example, with the mounting system 100 assembled
and coupled to the left gearbox coupling bore 72a, the left mount 72 may be positioned
between the left lugs 76, 78. With the left coupling bores 80a, 80b coaxially aligned
with the sleeve bores 148, the bolt 82 is inserted through the mounting system 100
to couple the gearbox 12 to the gas turbine engine 10 at the left mount 72.
[0050] With the gearbox 12 coupled to the gas turbine engine 10 via the mounting system
100 associated with each of the left mount 72 and the right mount 74, in the instance
that the gas turbine engine 10 undergoes a vibration, the resulting load from the
vibration is transferred to the mounting system 100. In instances of low loads, such
as less than about 2000 pound-force (Ibf), the damping member 142 undergoes a low
deflection, such as less than about 0.15 inches (in.), which enables the damping member
142 to provide less load transfer to the gearbox 12 as the damping member 142 is able
to provide a higher amount of damping. In instances of higher loads, such as greater
than or equal to about 2000 pound-force (Ibf), the corrugated bushings 106, 306, 406
share the load with the damping member 142, which enables the damping member 142 to
also undergo a low deflection, such as less than about 0.15 inches (in.). The low
deflection of the damping member 142 during the application of high loads enables
the damping member 142 to provide less load transfer to the gearbox 12 as the damping
member 142 is able to provide higher damping due to the load sharing with the corrugated
bushings 106, 306, 406. In addition, by sharing the load with the corrugated bushings
106, 306, 406, a life of the damping members 142 is improved. Generally, the corrugated
bushings 106, 306, 406 provide load sharing at about a 20% compression of the damping
member 142. By providing the corrugated bushings 106, 306, 406 parallel to the damping
members 142 within the engine coupling bore 136, the corrugated bushings 106, 306,
406 also provide for damping of the loads experienced by a vibration of the gas turbine
engine 10.
[0051] It should be noted that while the mounting system 100 is described herein as including
two of the corrugated bushings 106, 306, 406, the mounting system 100 may include
one of the corrugated bushings 106 and one of the corrugated bushings 306 or 406,
and thus, any combination of corrugated bushings 106, 306, 406 may be employed to
share the load experienced by the mounting system 100. In addition, while the corrugated
bushings 106, 306, 406 are illustrated herein with the corrugations 174, 374, 474,
a second bushing for use with the mounting system 100 may be substantially smooth
and define at least one hollow chamber, if desired for the particular application.
[0052] In this document, relational terms such as first and second, and the like may be
used solely to distinguish one entity or action from another entity or action without
necessarily requiring or implying any actual such relationship or order between such
entities or actions. Numerical ordinals such as "first," "second," "third," etc. simply
denote different singles of a plurality and do not imply any order or sequence unless
specifically defined by the claim language. The sequence of the text in any of the
claims does not imply that process steps must be performed in a temporal or logical
order according to such sequence unless it is specifically defined by the language
of the claim. The process steps may be interchanged in any order without departing
from the scope of the invention as long as such an interchange does not contradict
the claim language and is not logically nonsensical.
[0053] While at least one exemplary embodiment has been presented in the foregoing detailed
description, it should be appreciated that a vast number of variations exist. It should
also be appreciated that the exemplary embodiment or exemplary embodiments are only
examples, and are not intended to limit the scope, applicability, or configuration
of the disclosure in any way. Rather, the foregoing detailed description will provide
those skilled in the art with a convenient road map for implementing the exemplary
embodiment or exemplary embodiments. It should be understood that various changes
can be made in the function and arrangement of elements without departing from the
scope of the disclosure as set forth in the appended claims and the legal equivalents
thereof.
1. A mounting system for coupling a gearbox to an engine, comprising:
a sleeve including a first sleeve end opposite a second sleeve end, an outer perimeter
and a sleeve bore defined through the sleeve from the first sleeve end to the second
sleeve end;
a damping member coupled about the outer perimeter of the sleeve at the first sleeve
end; and
a corrugated bushing coupled about the outer perimeter of the sleeve between the damping
member and the second sleeve end.
2. The mounting system of Claim 1, wherein the corrugated bushing has a bushing outer
perimeter and a bushing inner perimeter, and at least one chamber is defined between
the bushing outer perimeter and the bushing inner perimeter.
3. The mounting system of Claim 2, wherein the at least one chamber comprises a plurality
of hollow chambers that are spaced apart about the bushing outer perimeter.
4. The mounting system of Claim 2, wherein the at least one chamber comprises a plurality
of hollow chambers that are spaced apart axially from a first bushing end to a second
bushing end of the corrugated bushing.
5. The mounting system of Claim 1, wherein the corrugated bushing defines a plurality
of undulations that extend tangentially about a bushing outer perimeter of the corrugated
bushing.
6. The mounting system of Claim 1, wherein the corrugated bushing defines a plurality
of undulations that extend axially along a bushing outer perimeter of the corrugated
bushing from a first bushing end to a second bushing end.
7. The mounting system of Claim 1, wherein the corrugated bushing includes a plurality
of corrugations, each of the plurality of corrugations includes a sidewall, a first
ramp surface coupled to the sidewall and a second ramp surface coupled to the first
ramp surface, and the second ramp surface is coupled to the sidewall of an adjacent
one of the plurality of corrugations.
8. The mounting system of Claim 7, wherein the sidewall includes a plurality of undulations.
9. The mounting system of Claim 7, wherein the sidewall is planar.
10. The mounting system of Claim 1, wherein the corrugated bushing includes a plurality
of corrugations defined on a sheet that defines a bushing outer perimeter of the corrugated
bushing, each of the plurality of corrugations includes a first ramp surface and a
second ramp surface coupled to the first ramp surface, and the sheet is coupled to
a bushing sleeve that defines a bushing inner perimeter of the corrugated bushing
by a plurality of sidewalls.
11. The mounting system of Claim 10, wherein each of the plurality of sidewalls includes
a plurality of undulations.
12. The mounting system of Claim 1, further comprising a mounting housing that defines
a coupling bore and a second coupling bore, the sleeve, the damping member and the
corrugated bushing are each configured to be received within the coupling bore such
that the outer perimeter of the sleeve faces an inner diameter of the coupling bore
and a bushing outer perimeter of the corrugated bushing is spaced apart from the inner
diameter of the coupling bore, the coupling bore configured to couple the mounting
system to the engine and the second coupling bore is configured to couple the mounting
system to the gearbox.
13. The mounting system of Claim 1, wherein the corrugated bushing includes a bushing
sleeve that defines a bushing inner perimeter of the corrugated bushing and a plurality
of corrugations that define a bushing outer perimeter of the corrugated bushing, the
bushing sleeve is coupled about the sleeve and the bushing sleeve is coupled to the
plurality of corrugations by a plurality of sidewalls, each of the plurality of sidewalls
includes a plurality of undulations and each of the plurality of undulations includes
at least a first sidewall peak, a second sidewall peak and a trough defined between
the first sidewall peak and the second sidewall peak in a clockwise direction.
14. The mounting system of Claim 1, further comprising the gearbox and the gearbox defines
a gearbox coupling bore configured to receive the mounting system such that the bushing
outer perimeter of the corrugated bushing is spaced apart from an inner diameter of
the gearbox coupling bore.